you can connect to your databaes by navicat and open the table "mob_proto" in your "player"-database. Then you can look for the column named "exp". change this manual or use a mysql dump for changing ist automatically.
Here you have the dump:
Code:
UPDATE player.mob_proto SET exp=exp*2 ;
You can change *2 to *3 oder *4. You can change it to +1 or /2 like everything you want to have :P
And for gold you can us this:
Code:
UPDATE player.mob_proto SET gold_min=gold_min*2 , gold_max=gold_max*2 ;